A single Systemd command can cripple your Linux system

Despite the open availability of its code, hacking Linux platform is quite tough for novices. However, a short Systemd command has now emerged online to let anyone cripple your Linux system.

System administrator Andrew Ayer has discovered the tiny command that can fit in a single 140-character tweet but affects various Linux distributions including CentOS, Debian and CentOS. The command is capable of collapsing the Linux system the moment it appears on the screen — without requiring root access. Interestingly, this bug is not new and has lived hiddenly for more than two years.

“The immediate question raised by this bug is what kind of quality assurance process would allow such a simple bug to exist for over two years,” writes Ayer, while describing the Systemd command in a detailed blog post.

It has found that the single command is not affecting all Linux systems in the same manner. While it simply hangs PID 1 in pause system call in some instances, the addition of ‘while true’ loop makes the system crippled in all other cases.

Canonical recently released a security update that patched Systemd to resist the system crippling bug in Ubuntu 16.04 LTS. Likewise, CentOS, Debian and other popular Linux distributions are expected to receive similar over-the-air fixes in the coming future.

In the meantime, Arey advised developers to avoid using some non-standard interfaces of Systemd to get a clean, bug-free experience.